• 환경영향평가
• /
• 제22권3호
• /
• pp.219-230
• /
• 2013

Species distribution modeling is one of the most effective habitat analysis methods for wildlife conservation. This study was for evaluating the suitability of species distribution to distance between forest patches in Seoul city using tits. We analyzed the distribution of the four species of tits: varied tit (Parus varius), marsh tit (P. palustris), great tit (P. major) and coal tit (P. ater), using the landscape indexes and connectivity indexes, and compared the resulting suitability indexes from 100m to 1,000m. As factors affecting to the distribution of tits, we calculated landscape indices by separating them into intra-patch indices (i.e. logged patch area (PA), area-weighted mean patch shape index (PSI), tree rate (TR)) and inter-patch indices (i.e. patch degree (PD), patch betweenness (PB), difference probability of connectivity (DPC)), to analyze the internal properties of the patches and their connectivity by tits occurrence data using logistic regression modeling. The models were evaluated by AICc (Akaike Information Criteria with a correction for finite sample sizes) and AUC (Area Under Curve of ROC). The results of AICc and AUC showed DPC, PA, PSI, and TR were important factors of the habitat models for great tit and marsh tit at the level of distance 500~800m. In contrast, habitat models for coal tit and varied tit, which are known as forest interior species, reflected PA, PSI, and TR as intra-patch indices rather than connectivity. These mean that coal tit and varied tit are more likely to find a large circular forest patch than a small and long-shaped forest patch, which are higher rate of forest. Therefore, different strategies are required in order to enhance the habitats of the forest birds, tits, in a region that has fragmented forest patches such as Seoul city. It is important to manage forest interior areas for coal tit and varied tit, which are known as forest interior species and to manage not only forest interior areas but also connectivity of the forest patches in the threshold distance for great tit and marsh tit as adapted species to the urban ecosystem for sustainable ecosystem management.

• 인터넷정보학회논문지
• /
• 제8권3호
• /
• pp.1-7
• /
• 2007

1994년 미국에서 최초의 디지털 방송인 DirectTV 서비스를 시작하여, 현재 다양한 방송 서비스 분야로 확산되고 있다. 국내에서는 새마을 열차, 지하철 일부 구간에 TIT(Tranport Information Technology) 기술 기반의 IP-TV 방송 서비스를 제공하고 있다. 그러나, 구동 S/W가 교차형 연동 실행되어 프로그램의 실행이 정지되거나, 교차 실행 시간 구간에서 메모리 누수 및 오버플로우가 빈번히 발생되고 있다. 이러한 실행시 발생되는 시스템 Fault는 재생 손실 시간을 가중시켜 방송 서비스의 신뢰성 약화의 주요한 원인이 되고 있다. 본 논문에서는 물리적 실행 환경이 열악한 TIT 기반의 IP-TV 플랫폼을 감시하기 위해 모니터링 시간 구간을 형식화하고, S/W 기반의 TIT Monitor를 설계 및 구현하였다. 그리고 적용 실험을 통해 14.3%의 재생 시간이 향상되었음을 알 수 있었다.

• 인터넷정보학회논문지
• /
• 제8권5호
• /
• pp.59-66
• /
• 2007

국내에서는 새마을 열차, 지하철 일부 구간에 TIT 기술 기반의 IP-TV 방송 서비스를 제공되고 있으나, 교차 실행 시간 구간에서 메모리 누수 및 오버플로우가 빈번히 발생되어 서비스의 신뢰성 약화에 주요한 원인이 되고 있다. 본 논문에서는 물리적 실행 환경이 열악한 TIT 기반의 IP-TV 플랫폼의 연속 동작의 신뢰성을 향상시키기 위해 Monitoring module과 Reset module을 개발하고 재생 시간이 실험을 통해 7.2% 향상시킬 수 있었다. 특히, Monitoring module은 기존 시스템(8)의 문제점인 S/W Fault에 기인된 Dead Lock 상태를 극복하기 위해 H/W기반의 Reset Module을 추가하여 서비스 차원의 결함 허용(Fault Tolerance)을 제공하였다.

• The Korean Journal of Ecology
• /
• 제22권2호
• /
• pp.65-68
• /
• 1999

In December-January of 1996-1997 and 1997-1998, information was gathered about vertical distribution of foraging sites of tits in 34 flocks in coniferous and deciduous forests. There was a significant effect of forest type on the distribution of foraging sites of each species. Habitat was classified into 5 height layers vertically: ground, bushes (usually＜1.5 m, up to 3 m), tree layer 1 (up to 1/3 of tree height), tree layer 2 (1/3-2/3 tree height). and tree layer 3 (＞2/3 tree height). There were differences among species: great tit (Parus major) foraged mostly on the ground, coal tit (P. ater) and long-tailed tit (Acrocephalus caudatus) - on the highest tree layer, marsh tit (P. palustris) was often seen on bushes, and varied tit (P. varius) - in tree layer 2. Smaller species used upper and outer parts of trees. suggesting that, like in most other similar studies. larger dominant species prevented smaller species from using inner parts of trees.

• International Journal of Air-Conditioning and Refrigeration
• /
• 제17권4호
• /
• pp.141-148
• /
• 2009

Afterfogging of the regenerative gas turbine system has an advantage over inlet fogging in that the high outlet temperature of air compressor makes the injection of more water and the recuperation of more exhaust heat possible. This study investigates the effects of turbine inlet temperature (TIT) on the performance of regenerative gas turbine system with afterfogging through a thermodynamic analysis model. For the standard ambient conditions and the water injection ratios up to 5%, the variation of system performance including the thermal efficiency is numerically analyzed with respect to the variations of TIT and pressure ratio. It is also analyzed how the maximum thermal efficiency, net specific work, and pressure ratio itself change with TIT at the peak points of thermal efficiency curve. All of these are found to increase almost linearly with the increases of both TIT and water injection ratio.

• 한국유체기계학회 논문집
• /
• 제19권5호
• /
• pp.61-67
• /
• 2016

Turbine blade cooling is one of the major technologies to enhance the performance of gas turbine and combined cycle power plants. In this study, two cases of coolant pre-cooling schemes were applied in combined cycle power plant: decrease of coolant mass flow needed to cool turbine blade and increase of turbine inlet temperature (TIT). Both schemes are benefited by the decrease of coolant temperature through coolant pre-cooling. Under the same degree of pre-cooling, increasing TIT exhibits larger plant power boost and higher plant efficiency than reducing coolant flow. As a result, the former produces the same gas turbine power with a much smaller degree of pre-cooling than the latter. Another advantage of increasing TIT is a higher plant efficiency. Even with an assumption of partial achievement of the theoretically predicted TIT, the method of increasing TIT can provide considerably larger power output.

• 한국컴퓨터정보학회논문지
• /
• 제7권4호
• /
• pp.174-181
• /
• 2002

본 논문에서는 기존의 셀 간격 제어기에서 방출되는 셀의 시간을 참조하는 RDT 방식에서의 지연 누적을 보완하면서 RDT의 장점을 활용하기 위하여 RAT의 방식에서 적용한 것과 같이 셀 도착 시간을 기준으로 하며, 간격 제어기에서 따로 데이터 버퍼를 두지 않고 시스템 내의 데이터 버퍼를 사용하여 셀들을 저장하고 저장된 셀들을 재방출하는 논리적 출발시간 TIT(theoretical inter-arrival time)를 이용하는 방식을 제안한다.

• The Korean Journal of Ecology
• /
• 제18권3호
• /
• pp.299-305
• /
• 1995

Feeding activites during nestling period of Coal tit (Parus ater) were studied at breeding sites in Mt. Chiri. The average feeding frequency per hour of female Coal tit exceeded that of the male. The average excrement-cleaning frequency per hour of female exceeded that of male, with a longer feed duration. The feeding frequency per hour was generally higher in the morning, and the female exceeded the male in the frquency. It is shown that male of the Coal tit in nestling period played a major role in territorial defense compared with female.

• 한국동물학회지
• /
• 제38권2호
• /
• pp.230-237
• /
• 1995

Playback experiments were excecuted with seven threat Tit males inhabited in Gsngnae Myeon, Darak Ri, Chungbuk province to investigate the signal value of partial song (one unit phrase composed of two notes) as a species recognition releaser. Territorial males responded strongly to their own natural, synthetic and partial songs played in the field. However, thew showed weak or no responses to the playback songs of other species: Coal Tit (Porus ate4 and Yellow-throated Bunting (EmberiEa elegansl.6reat Tits distinguished conspecific partial songs readily from songs of other species. The results demonstrated that one unit phrase which is a basic arrangement of the Great Tit song, containes information on species recognition.

• 한국산림과학회지
• /
• 제9권1호
• /
• pp.49-54
• /
• 1969

솔잎혹파리 유충의 포식성 조류를 조사하기 위하여 1967년부터 1968년까지 솔잎혹파리 유충의 낙하최성기인 10월 15일부터 11월 30일까지 조류 380개체 (1967년 182개체, 1968 년 198개체)를 포획하여 위(胃)내용물을 조사한것이다. 1. 솔잎혹파리 유충이 지표로 낙하하는 시기에 이를 많이 포식하는 새들은 박새, 쇠박새, 진박새, 곤줄박이, 오목눈이, 쑥새, 노란턱멧새, 꼬까참새, 상모솔새등이였다. 2. 조류별 솔잎혹파리 유충의 평균 포식수는 1967년도에 쑥새가 108마리, 쇠박새 64마리, 박새 25마리였고 1968년도에는 진박새 36마리, 박새 28마리, 쇠박새 17마리였다 3. 솔잎혹파리 포식성 조류의 포식량은 솔잎혹파리 유충의 시기별 낙하율과 일치하였으며 솔잎혹파리가 많이 지표로 떨어지는 11월초중순에 가장 많았다 4. 포획한 조류 380개체의 위(胃)를 분석조사한 바 솔잎혹파리 유충을 포식한 개체는 157개체 (1967년 53개체, 1968년 104개체)였다.